Enhanced steering operation

Patent metadata

Field	Value
Publication number	US-9975573-B2
Application number	US-201615223115-A
Country	US
Kind code	B2
Filing date	Jul 29, 2016
Priority date	Jul 29, 2016
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

An operation mode of a first actuator engaged with a steering rack is determined. An operation mode of a second actuator engaged with a steering column is determined. The operation mode of one of the first and second actuators is adjusted upon detecting a failure in the other of the first and second actuators. At least one of the steering rack and the steering column is actuated based on the operation mode. In an angle control mode, a predetermined steering angle is provided to the first and second actuators to adjust the steering rack according to the steering angle. In a torque control mode, a steering column torque from a torsion sensor disposed on the steering column is provided to the first and second actuators to adjust the steering rack according to the steering column torque.

First claim

The invention claimed is:

1. A system, comprising a computer including a processor and a memory, the memory storing instructions executable by the computer to:
determine an operation mode of a first actuator engaged with a steering rack;
determine an operation mode of a second actuator engaged with a steering column;
adjust the operation mode of one of the first and second actuators upon detecting a failure in the other of the first and second actuators;
actuate at least one of the steering rack and the steering column based on the operation mode; and
provide, in an angle control mode, a predetermined steering angle to the first and second actuators and to adjust the steering rack according to the steering angle, and to provide, in a torque control mode, a steering column torque from a torsion sensor disposed on the steering column to the first and second actuators, and to adjust the steering rack according to the steering column torque.

2. The system of claim 1 , wherein the instructions further include instructions to adjust the operation mode of the second actuator to the torque control mode upon detecting the failure in the first actuator.

3. The system of claim 2 , wherein the instructions further include instructions to adjust the operation mode of the second actuator to the angle control mode when a virtual operator operates the steering column in a fully autonomous mode.

4. The system of claim 1 , wherein the instructions further include instructions to adjust the operation mode of the first actuator to the angle control mode upon detecting the failure in the second actuator.

5. The system of claim 4 , wherein the instructions further include instructions to disengage a clutch when the first actuator is in the angle control mode.

6. The system of claim 1 , wherein the first actuator is attached to a rotation mechanism rotatably engaged with the steering rack and the instructions further include instructions to rotate the rotation mechanism according to the predetermined steering angle when the first actuator is in the angle control mode.

7. The system of claim 1 , wherein the second actuator is attached to a rotation mechanism engaged with the steering column and the instructions further include instructions to rotate the rotation mechanism to reduce the steering column torque determined by the torsion sensor when the second actuator is in the torque control mode.

8. The system of claim 1 , wherein the instructions further include instructions to adjust the operation mode of the first actuator to the torque control mode and to adjust the operation mode of the second actuator to the angle control mode when both the first and second actuators are operational.

9. The system of claim 1 , wherein the instructions further include instructions to disengage a clutch when both the first and second actuators are in the angle control mode.

10. The system of claim 1 , wherein the instructions further include instructions to disengage a clutch, to actuate the first actuator to move the steering rack a predetermined distance, and to actuate the second actuator to rotate the steering column to an angle based on the predetermined distance of the steering rack.

11. A method, comprising:
determining an operation mode of a first actuator engaged with a steering rack;
determining an operation mode of a second actuator engaged with a steering column;
adjusting the operation mode of one of the first and second actuators upon detecting a failure in the other of the first and second actuators;
actuating at least one of the steering rack and the steering column based on the operation mode; and
providing, in an angle control mode, a predetermined steering angle to the first and second actuators and to adjust the steering rack according to the steering angle, and providing, in a torque control mode, a steering column torque from a torsion sensor disposed on the steering column to the first and second actuators, and to adjust the steering rack according to the steering column torque.

12. The method of claim 11 , further comprising adjusting the operation mode of the second actuator to the torque control mode upon detecting the failure in the first actuator.

13. The method of claim 12 , further comprising adjusting the operation mode of the second actuator to the angle control mode when a virtual operator operates the steering column in a fully autonomous mode.

14. The method of claim 11 , further comprising adjusting the operation mode of the first actuator to the angle control mode upon detecting the failure in the second actuator.

15. The method of claim 14 , further comprising disengaging a clutch when the first actuator is in the angle control mode.

16. The method of claim 11 , wherein the first actuator is attached to a rotation mechanism rotatably engaged with the steering rack and the method further comprises rotating the rotation mechanism according to the predetermined steering angle when the first actuator is in the angle control mode.

17. The method of claim 11 , wherein the second actuator is attached to a rotation mechanism engaged with the steering column and the method further comprises rotating the rotation mechanism to reduce the steering column torque determined by the torsion sensor when the second actuator is in the torque control mode.

18. The method of claim 11 , further comprising adjusting the operation mode of the first actuator to the torque control mode and adjusting the operation mode of the second actuator to the angle control mode when both the first and second actuators are operational.

19. The method of claim 11 , further comprising disengaging a clutch when both the first and second actuators are in the angle control mode.

20. The method of claim 11 , further comprising disengaging a clutch, actuating the first actuator to move the steering rack a predetermined distance, and actuating the second actuator to rotate the steering column to an angle based on the predetermined distance of the steering rack.

Assignees

• Ford Global Tech Llc

Inventors

• She Eric
• Rolfes Nathaniel Abram
• Bouse William James

Classifications

• B62D5/003

  Backup systems, e.g. for manual steering (B62D5/30 takes precedence) · CPC title

• B62D5/0481

  monitoring the steering system, e.g. failures · CPC title

• B62D5/0472

  for damping vibrations · CPC title

• B62D5/006

  power actuated · CPC title

• B62D3/00

  Steering gears (power assisted or power driven B62D5/00; steering linkages B62D7/00; for non-deflectable wheels B62D11/00; gearing in general F16H) · CPC title